Intramuscular Versus Intravenous SARS-CoV-2 Neutralizing Antibody Sotrovimab for Treatment of COVID-19 (COMET-TAIL): A Randomized Non-inferiority Clinical Trial (preprint)

Background: Convenient administration of coronavirus disease 2019 (COVID-19) treatment in community settings is desirable. Sotrovimab is a pan-sarbecovirus dual-action monoclonal antibody formulated for intravenous (IV) or intramuscular (IM) administration for early treatment of mild/moderate COVID-19. Methods: This phase 3, randomized, multicenter, open-label study tested non-inferiority of IM to IV administration using a 3.5% absolute non-inferiority margin. From June to August 2021, patients aged [≥]12 years with COVID-19, not hospitalized or receiving supplemental oxygen, and at high risk for progression were randomized 1:1:1 to a single 500-mg IV sotrovimab infusion or 500-mg or 250-mg IM sotrovimab injection. The primary composite endpoint was progression to all-cause hospitalization for >24 hours for acute management of illness or all-cause death through day 29. Results: Sotrovimab 500 mg IM was non-inferior to 500 mg IV: 10/376 (2.7%) participants in the sotrovimab 500-mg IM group versus 5/378 (1.3%) in the sotrovimab 500-mg IV group met the primary endpoint (absolute adjusted risk difference: 1.06% [95% confidence interval [CI]: -1.15%, 3.26%]). The CI upper limit was lower than the prespecified non-inferiority margin of 3.5%. 250-mg IM group enrollment was discontinued early because a greater proportion of hospitalizations was seen in that group versus the 500-mg groups. Serious adverse events occurred in <1% to 2% of participants across groups. Four participants experienced serious disease related events and died (500 mg IM: 2/393 [<1%]; 250 mg IM: 2/195 [1%]). Conclusions: Sotrovimab 500-mg IM injection was well tolerated and non-inferior to IV administration. IM administration could expand outpatient treatment access for COVID-19.

Effect of the Neutralizing SARS-CoV-2 Antibody Sotrovimab in Preventing Progression of COVID-19: A Randomized Clinical Trial (preprint)

Importance: Older patients and those with underlying comorbidities infected with SARS-CoV-2 may be at increased risk of hospitalization and death from COVID-19. Sotrovimab is a neutralizing antibody designed for treatment of high-risk patients to prevent COVID-19 progression. Objective: To evaluate the efficacy and safety of sotrovimab in preventing progression of mild to moderate COVID-19 to severe disease. Design: Randomized, double-blind, multicenter, placebo-controlled, phase 3 study. Setting: 57 centers in 5 countries. Participants: Nonhospitalized patients with symptomatic, mild to moderate COVID-19 and at least 1 risk factor for disease progression. Intervention: Patients were randomized (1:1) to an intravenous infusion of sotrovimab 500 mg or placebo. Main Outcomes and Measures: The primary efficacy outcome was the proportion of patients with COVID-19 progression, defined as all-cause hospitalization longer than 24 hours for acute illness management or death through day 29. Key secondary outcomes included the proportion of patients with COVID-19 progression, defined as emergency room visit, hospitalization of any duration, or death, and proportion of patients developing severe/critical respiratory COVID-19 requiring supplemental oxygen. Results: Among 1057 patients randomized (sotrovimab, 528; placebo, 529), all-cause hospitalization longer than 24 hours or death was significantly reduced with sotrovimab (6/528 [1%]) vs placebo (30/529 [6%]) by 79% (95% CI, 50% to 91%; P